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      1 /*
      2 *******************************************************************************
      3 * Copyright (c) 1996-2015, International Business Machines Corporation
      4 *               and others. All Rights Reserved.
      5 *******************************************************************************
      6 * File unorm.h
      7 *
      8 * Created by: Vladimir Weinstein 12052000
      9 *
     10 * Modification history :
     11 *
     12 * Date        Name        Description
     13 * 02/01/01    synwee      Added normalization quickcheck enum and method.
     14 */
     15 #ifndef UNORM_H
     16 #define UNORM_H
     17 
     18 #include "unicode/utypes.h"
     19 
     20 #if !UCONFIG_NO_NORMALIZATION
     21 
     22 #include "unicode/uiter.h"
     23 #include "unicode/unorm2.h"
     24 
     25 #ifndef U_HIDE_DEPRECATED_API
     26 
     27 /**
     28  * \file
     29  * \brief C API: Unicode Normalization
     30  *
     31  * Old Unicode normalization API.
     32  *
     33  * This API has been replaced by the unorm2.h API and is only available
     34  * for backward compatibility. The functions here simply delegate to the
     35  * unorm2.h functions, for example unorm2_getInstance() and unorm2_normalize().
     36  * There is one exception: The new API does not provide a replacement for unorm_compare().
     37  * Its declaration has been moved to unorm2.h.
     38  *
     39  * <code>unorm_normalize</code> transforms Unicode text into an equivalent composed or
     40  * decomposed form, allowing for easier sorting and searching of text.
     41  * <code>unorm_normalize</code> supports the standard normalization forms described in
     42  * <a href="http://www.unicode.org/unicode/reports/tr15/" target="unicode">
     43  * Unicode Standard Annex #15: Unicode Normalization Forms</a>.
     44  *
     45  * Characters with accents or other adornments can be encoded in
     46  * several different ways in Unicode.  For example, take the character A-acute.
     47  * In Unicode, this can be encoded as a single character (the
     48  * "composed" form):
     49  *
     50  * \code
     51  *      00C1    LATIN CAPITAL LETTER A WITH ACUTE
     52  * \endcode
     53  *
     54  * or as two separate characters (the "decomposed" form):
     55  *
     56  * \code
     57  *      0041    LATIN CAPITAL LETTER A
     58  *      0301    COMBINING ACUTE ACCENT
     59  * \endcode
     60  *
     61  * To a user of your program, however, both of these sequences should be
     62  * treated as the same "user-level" character "A with acute accent".  When you are searching or
     63  * comparing text, you must ensure that these two sequences are treated
     64  * equivalently.  In addition, you must handle characters with more than one
     65  * accent.  Sometimes the order of a character's combining accents is
     66  * significant, while in other cases accent sequences in different orders are
     67  * really equivalent.
     68  *
     69  * Similarly, the string "ffi" can be encoded as three separate letters:
     70  *
     71  * \code
     72  *      0066    LATIN SMALL LETTER F
     73  *      0066    LATIN SMALL LETTER F
     74  *      0069    LATIN SMALL LETTER I
     75  * \endcode
     76  *
     77  * or as the single character
     78  *
     79  * \code
     80  *      FB03    LATIN SMALL LIGATURE FFI
     81  * \endcode
     82  *
     83  * The ffi ligature is not a distinct semantic character, and strictly speaking
     84  * it shouldn't be in Unicode at all, but it was included for compatibility
     85  * with existing character sets that already provided it.  The Unicode standard
     86  * identifies such characters by giving them "compatibility" decompositions
     87  * into the corresponding semantic characters.  When sorting and searching, you
     88  * will often want to use these mappings.
     89  *
     90  * <code>unorm_normalize</code> helps solve these problems by transforming text into the
     91  * canonical composed and decomposed forms as shown in the first example above.
     92  * In addition, you can have it perform compatibility decompositions so that
     93  * you can treat compatibility characters the same as their equivalents.
     94  * Finally, <code>unorm_normalize</code> rearranges accents into the proper canonical
     95  * order, so that you do not have to worry about accent rearrangement on your
     96  * own.
     97  *
     98  * Form FCD, "Fast C or D", is also designed for collation.
     99  * It allows to work on strings that are not necessarily normalized
    100  * with an algorithm (like in collation) that works under "canonical closure", i.e., it treats precomposed
    101  * characters and their decomposed equivalents the same.
    102  *
    103  * It is not a normalization form because it does not provide for uniqueness of representation. Multiple strings
    104  * may be canonically equivalent (their NFDs are identical) and may all conform to FCD without being identical
    105  * themselves.
    106  *
    107  * The form is defined such that the "raw decomposition", the recursive canonical decomposition of each character,
    108  * results in a string that is canonically ordered. This means that precomposed characters are allowed for as long
    109  * as their decompositions do not need canonical reordering.
    110  *
    111  * Its advantage for a process like collation is that all NFD and most NFC texts - and many unnormalized texts -
    112  * already conform to FCD and do not need to be normalized (NFD) for such a process. The FCD quick check will
    113  * return UNORM_YES for most strings in practice.
    114  *
    115  * unorm_normalize(UNORM_FCD) may be implemented with UNORM_NFD.
    116  *
    117  * For more details on FCD see the collation design document:
    118  * http://source.icu-project.org/repos/icu/icuhtml/trunk/design/collation/ICU_collation_design.htm
    119  *
    120  * ICU collation performs either NFD or FCD normalization automatically if normalization
    121  * is turned on for the collator object.
    122  * Beyond collation and string search, normalized strings may be useful for string equivalence comparisons,
    123  * transliteration/transcription, unique representations, etc.
    124  *
    125  * The W3C generally recommends to exchange texts in NFC.
    126  * Note also that most legacy character encodings use only precomposed forms and often do not
    127  * encode any combining marks by themselves. For conversion to such character encodings the
    128  * Unicode text needs to be normalized to NFC.
    129  * For more usage examples, see the Unicode Standard Annex.
    130  */
    131 
    132 #ifndef U_HIDE_DEPRECATED_API
    133 /**
    134  * Constants for normalization modes.
    135  * @deprecated ICU 56 Use unorm2.h instead.
    136  */
    137 typedef enum {
    138   /** No decomposition/composition. @deprecated ICU 56 Use unorm2.h instead. */
    139   UNORM_NONE = 1,
    140   /** Canonical decomposition. @deprecated ICU 56 Use unorm2.h instead. */
    141   UNORM_NFD = 2,
    142   /** Compatibility decomposition. @deprecated ICU 56 Use unorm2.h instead. */
    143   UNORM_NFKD = 3,
    144   /** Canonical decomposition followed by canonical composition. @deprecated ICU 56 Use unorm2.h instead. */
    145   UNORM_NFC = 4,
    146   /** Default normalization. @deprecated ICU 56 Use unorm2.h instead. */
    147   UNORM_DEFAULT = UNORM_NFC,
    148   /** Compatibility decomposition followed by canonical composition. @deprecated ICU 56 Use unorm2.h instead. */
    149   UNORM_NFKC =5,
    150   /** "Fast C or D" form. @deprecated ICU 56 Use unorm2.h instead. */
    151   UNORM_FCD = 6,
    152 
    153   /** One more than the highest normalization mode constant. @deprecated ICU 56 Use unorm2.h instead. */
    154   UNORM_MODE_COUNT
    155 } UNormalizationMode;
    156 #endif  /* U_HIDE_DEPRECATED_API */
    157 
    158 /**
    159  * Constants for options flags for normalization.
    160  * Use 0 for default options,
    161  * including normalization according to the Unicode version
    162  * that is currently supported by ICU (see u_getUnicodeVersion).
    163  * @deprecated ICU 56 Use unorm2.h instead.
    164  */
    165 enum {
    166     /**
    167      * Options bit set value to select Unicode 3.2 normalization
    168      * (except NormalizationCorrections).
    169      * At most one Unicode version can be selected at a time.
    170      * @deprecated ICU 56 Use unorm2.h instead.
    171      */
    172     UNORM_UNICODE_3_2=0x20
    173 };
    174 
    175 /**
    176  * Lowest-order bit number of unorm_compare() options bits corresponding to
    177  * normalization options bits.
    178  *
    179  * The options parameter for unorm_compare() uses most bits for
    180  * itself and for various comparison and folding flags.
    181  * The most significant bits, however, are shifted down and passed on
    182  * to the normalization implementation.
    183  * (That is, from unorm_compare(..., options, ...),
    184  * options>>UNORM_COMPARE_NORM_OPTIONS_SHIFT will be passed on to the
    185  * internal normalization functions.)
    186  *
    187  * @see unorm_compare
    188  * @deprecated ICU 56 Use unorm2.h instead.
    189  */
    190 #define UNORM_COMPARE_NORM_OPTIONS_SHIFT 20
    191 
    192 /**
    193  * Normalize a string.
    194  * The string will be normalized according the specified normalization mode
    195  * and options.
    196  * The source and result buffers must not be the same, nor overlap.
    197  *
    198  * @param source The string to normalize.
    199  * @param sourceLength The length of source, or -1 if NUL-terminated.
    200  * @param mode The normalization mode; one of UNORM_NONE,
    201  *             UNORM_NFD, UNORM_NFC, UNORM_NFKC, UNORM_NFKD, UNORM_DEFAULT.
    202  * @param options The normalization options, ORed together (0 for no options).
    203  * @param result A pointer to a buffer to receive the result string.
    204  *               The result string is NUL-terminated if possible.
    205  * @param resultLength The maximum size of result.
    206  * @param status A pointer to a UErrorCode to receive any errors.
    207  * @return The total buffer size needed; if greater than resultLength,
    208  *         the output was truncated, and the error code is set to U_BUFFER_OVERFLOW_ERROR.
    209  * @deprecated ICU 56 Use unorm2.h instead.
    210  */
    211 U_STABLE int32_t U_EXPORT2
    212 unorm_normalize(const UChar *source, int32_t sourceLength,
    213                 UNormalizationMode mode, int32_t options,
    214                 UChar *result, int32_t resultLength,
    215                 UErrorCode *status);
    216 
    217 /**
    218  * Performing quick check on a string, to quickly determine if the string is
    219  * in a particular normalization format.
    220  * Three types of result can be returned UNORM_YES, UNORM_NO or
    221  * UNORM_MAYBE. Result UNORM_YES indicates that the argument
    222  * string is in the desired normalized format, UNORM_NO determines that
    223  * argument string is not in the desired normalized format. A
    224  * UNORM_MAYBE result indicates that a more thorough check is required,
    225  * the user may have to put the string in its normalized form and compare the
    226  * results.
    227  *
    228  * @param source       string for determining if it is in a normalized format
    229  * @param sourcelength length of source to test, or -1 if NUL-terminated
    230  * @param mode         which normalization form to test for
    231  * @param status       a pointer to a UErrorCode to receive any errors
    232  * @return UNORM_YES, UNORM_NO or UNORM_MAYBE
    233  *
    234  * @see unorm_isNormalized
    235  * @deprecated ICU 56 Use unorm2.h instead.
    236  */
    237 U_STABLE UNormalizationCheckResult U_EXPORT2
    238 unorm_quickCheck(const UChar *source, int32_t sourcelength,
    239                  UNormalizationMode mode,
    240                  UErrorCode *status);
    241 
    242 /**
    243  * Performing quick check on a string; same as unorm_quickCheck but
    244  * takes an extra options parameter like most normalization functions.
    245  *
    246  * @param src        String that is to be tested if it is in a normalization format.
    247  * @param srcLength  Length of source to test, or -1 if NUL-terminated.
    248  * @param mode       Which normalization form to test for.
    249  * @param options    The normalization options, ORed together (0 for no options).
    250  * @param pErrorCode ICU error code in/out parameter.
    251  *                   Must fulfill U_SUCCESS before the function call.
    252  * @return UNORM_YES, UNORM_NO or UNORM_MAYBE
    253  *
    254  * @see unorm_quickCheck
    255  * @see unorm_isNormalized
    256  * @deprecated ICU 56 Use unorm2.h instead.
    257  */
    258 U_STABLE UNormalizationCheckResult U_EXPORT2
    259 unorm_quickCheckWithOptions(const UChar *src, int32_t srcLength,
    260                             UNormalizationMode mode, int32_t options,
    261                             UErrorCode *pErrorCode);
    262 
    263 /**
    264  * Test if a string is in a given normalization form.
    265  * This is semantically equivalent to source.equals(normalize(source, mode)) .
    266  *
    267  * Unlike unorm_quickCheck(), this function returns a definitive result,
    268  * never a "maybe".
    269  * For NFD, NFKD, and FCD, both functions work exactly the same.
    270  * For NFC and NFKC where quickCheck may return "maybe", this function will
    271  * perform further tests to arrive at a TRUE/FALSE result.
    272  *
    273  * @param src        String that is to be tested if it is in a normalization format.
    274  * @param srcLength  Length of source to test, or -1 if NUL-terminated.
    275  * @param mode       Which normalization form to test for.
    276  * @param pErrorCode ICU error code in/out parameter.
    277  *                   Must fulfill U_SUCCESS before the function call.
    278  * @return Boolean value indicating whether the source string is in the
    279  *         "mode" normalization form.
    280  *
    281  * @see unorm_quickCheck
    282  * @deprecated ICU 56 Use unorm2.h instead.
    283  */
    284 U_STABLE UBool U_EXPORT2
    285 unorm_isNormalized(const UChar *src, int32_t srcLength,
    286                    UNormalizationMode mode,
    287                    UErrorCode *pErrorCode);
    288 
    289 /**
    290  * Test if a string is in a given normalization form; same as unorm_isNormalized but
    291  * takes an extra options parameter like most normalization functions.
    292  *
    293  * @param src        String that is to be tested if it is in a normalization format.
    294  * @param srcLength  Length of source to test, or -1 if NUL-terminated.
    295  * @param mode       Which normalization form to test for.
    296  * @param options    The normalization options, ORed together (0 for no options).
    297  * @param pErrorCode ICU error code in/out parameter.
    298  *                   Must fulfill U_SUCCESS before the function call.
    299  * @return Boolean value indicating whether the source string is in the
    300  *         "mode/options" normalization form.
    301  *
    302  * @see unorm_quickCheck
    303  * @see unorm_isNormalized
    304  * @deprecated ICU 56 Use unorm2.h instead.
    305  */
    306 U_STABLE UBool U_EXPORT2
    307 unorm_isNormalizedWithOptions(const UChar *src, int32_t srcLength,
    308                               UNormalizationMode mode, int32_t options,
    309                               UErrorCode *pErrorCode);
    310 
    311 /**
    312  * Iterative normalization forward.
    313  * This function (together with unorm_previous) is somewhat
    314  * similar to the C++ Normalizer class (see its non-static functions).
    315  *
    316  * Iterative normalization is useful when only a small portion of a longer
    317  * string/text needs to be processed.
    318  *
    319  * For example, the likelihood may be high that processing the first 10% of some
    320  * text will be sufficient to find certain data.
    321  * Another example: When one wants to concatenate two normalized strings and get a
    322  * normalized result, it is much more efficient to normalize just a small part of
    323  * the result around the concatenation place instead of re-normalizing everything.
    324  *
    325  * The input text is an instance of the C character iteration API UCharIterator.
    326  * It may wrap around a simple string, a CharacterIterator, a Replaceable, or any
    327  * other kind of text object.
    328  *
    329  * If a buffer overflow occurs, then the caller needs to reset the iterator to the
    330  * old index and call the function again with a larger buffer - if the caller cares
    331  * for the actual output.
    332  * Regardless of the output buffer, the iterator will always be moved to the next
    333  * normalization boundary.
    334  *
    335  * This function (like unorm_previous) serves two purposes:
    336  *
    337  * 1) To find the next boundary so that the normalization of the part of the text
    338  * from the current position to that boundary does not affect and is not affected
    339  * by the part of the text beyond that boundary.
    340  *
    341  * 2) To normalize the text up to the boundary.
    342  *
    343  * The second step is optional, per the doNormalize parameter.
    344  * It is omitted for operations like string concatenation, where the two adjacent
    345  * string ends need to be normalized together.
    346  * In such a case, the output buffer will just contain a copy of the text up to the
    347  * boundary.
    348  *
    349  * pNeededToNormalize is an output-only parameter. Its output value is only defined
    350  * if normalization was requested (doNormalize) and successful (especially, no
    351  * buffer overflow).
    352  * It is useful for operations like a normalizing transliterator, where one would
    353  * not want to replace a piece of text if it is not modified.
    354  *
    355  * If doNormalize==TRUE and pNeededToNormalize!=NULL then *pNeeded... is set TRUE
    356  * if the normalization was necessary.
    357  *
    358  * If doNormalize==FALSE then *pNeededToNormalize will be set to FALSE.
    359  *
    360  * If the buffer overflows, then *pNeededToNormalize will be undefined;
    361  * essentially, whenever U_FAILURE is true (like in buffer overflows), this result
    362  * will be undefined.
    363  *
    364  * @param src The input text in the form of a C character iterator.
    365  * @param dest The output buffer; can be NULL if destCapacity==0 for pure preflighting.
    366  * @param destCapacity The number of UChars that fit into dest.
    367  * @param mode The normalization mode.
    368  * @param options The normalization options, ORed together (0 for no options).
    369  * @param doNormalize Indicates if the source text up to the next boundary
    370  *                    is to be normalized (TRUE) or just copied (FALSE).
    371  * @param pNeededToNormalize Output flag indicating if the normalization resulted in
    372  *                           different text from the input.
    373  *                           Not defined if an error occurs including buffer overflow.
    374  *                           Always FALSE if !doNormalize.
    375  * @param pErrorCode ICU error code in/out parameter.
    376  *                   Must fulfill U_SUCCESS before the function call.
    377  * @return Length of output (number of UChars) when successful or buffer overflow.
    378  *
    379  * @see unorm_previous
    380  * @see unorm_normalize
    381  *
    382  * @deprecated ICU 56 Use unorm2.h instead.
    383  */
    384 U_STABLE int32_t U_EXPORT2
    385 unorm_next(UCharIterator *src,
    386            UChar *dest, int32_t destCapacity,
    387            UNormalizationMode mode, int32_t options,
    388            UBool doNormalize, UBool *pNeededToNormalize,
    389            UErrorCode *pErrorCode);
    390 
    391 /**
    392  * Iterative normalization backward.
    393  * This function (together with unorm_next) is somewhat
    394  * similar to the C++ Normalizer class (see its non-static functions).
    395  * For all details see unorm_next.
    396  *
    397  * @param src The input text in the form of a C character iterator.
    398  * @param dest The output buffer; can be NULL if destCapacity==0 for pure preflighting.
    399  * @param destCapacity The number of UChars that fit into dest.
    400  * @param mode The normalization mode.
    401  * @param options The normalization options, ORed together (0 for no options).
    402  * @param doNormalize Indicates if the source text up to the next boundary
    403  *                    is to be normalized (TRUE) or just copied (FALSE).
    404  * @param pNeededToNormalize Output flag indicating if the normalization resulted in
    405  *                           different text from the input.
    406  *                           Not defined if an error occurs including buffer overflow.
    407  *                           Always FALSE if !doNormalize.
    408  * @param pErrorCode ICU error code in/out parameter.
    409  *                   Must fulfill U_SUCCESS before the function call.
    410  * @return Length of output (number of UChars) when successful or buffer overflow.
    411  *
    412  * @see unorm_next
    413  * @see unorm_normalize
    414  *
    415  * @deprecated ICU 56 Use unorm2.h instead.
    416  */
    417 U_STABLE int32_t U_EXPORT2
    418 unorm_previous(UCharIterator *src,
    419                UChar *dest, int32_t destCapacity,
    420                UNormalizationMode mode, int32_t options,
    421                UBool doNormalize, UBool *pNeededToNormalize,
    422                UErrorCode *pErrorCode);
    423 
    424 /**
    425  * Concatenate normalized strings, making sure that the result is normalized as well.
    426  *
    427  * If both the left and the right strings are in
    428  * the normalization form according to "mode/options",
    429  * then the result will be
    430  *
    431  * \code
    432  *     dest=normalize(left+right, mode, options)
    433  * \endcode
    434  *
    435  * With the input strings already being normalized,
    436  * this function will use unorm_next() and unorm_previous()
    437  * to find the adjacent end pieces of the input strings.
    438  * Only the concatenation of these end pieces will be normalized and
    439  * then concatenated with the remaining parts of the input strings.
    440  *
    441  * It is allowed to have dest==left to avoid copying the entire left string.
    442  *
    443  * @param left Left source string, may be same as dest.
    444  * @param leftLength Length of left source string, or -1 if NUL-terminated.
    445  * @param right Right source string. Must not be the same as dest, nor overlap.
    446  * @param rightLength Length of right source string, or -1 if NUL-terminated.
    447  * @param dest The output buffer; can be NULL if destCapacity==0 for pure preflighting.
    448  * @param destCapacity The number of UChars that fit into dest.
    449  * @param mode The normalization mode.
    450  * @param options The normalization options, ORed together (0 for no options).
    451  * @param pErrorCode ICU error code in/out parameter.
    452  *                   Must fulfill U_SUCCESS before the function call.
    453  * @return Length of output (number of UChars) when successful or buffer overflow.
    454  *
    455  * @see unorm_normalize
    456  * @see unorm_next
    457  * @see unorm_previous
    458  *
    459  * @deprecated ICU 56 Use unorm2.h instead.
    460  */
    461 U_STABLE int32_t U_EXPORT2
    462 unorm_concatenate(const UChar *left, int32_t leftLength,
    463                   const UChar *right, int32_t rightLength,
    464                   UChar *dest, int32_t destCapacity,
    465                   UNormalizationMode mode, int32_t options,
    466                   UErrorCode *pErrorCode);
    467 
    468 #endif  /* U_HIDE_DEPRECATED_API */
    469 #endif /* #if !UCONFIG_NO_NORMALIZATION */
    470 #endif
    471